The present invention relates to sheet fabrication centers and machines such as for example turret punch presses, and more particularly to a new generation sheet fabricating machine that utilizes servo motors as its driver mechanisms for optimally effecting work on worksheets with less noise.
Publications U.S. Pat. No. 5,092,151 and U.S. Pat. No. 5,199,293 disclose particularly sheet working centers intended for bending, whereby separate means are used for accomplishing the approaching movement of the tool on one hand, and the actual working movement on the other hand. The means for accomplishing the approaching movement to the tool are constructed in a way that the approaching movement is relatively quick, and on the other hand, the means for accomplishing the actual working movement are constructed in a way that their movement is relatively slow in relation to the movement of the first means. On the other hand, the second means are constructed so that the force effect to be accomplished with them is considerably greater for the working of the sheet than the force effect accomplished by the movement of the first means which accomplish only a linear movement.
In said US publication, the second means comprise a first gliding means fixed to a buffer arranged to be movable in the vertical direction, and a second gliding means arranged to move by actuators in the horizontal direction, wherein the working movement of the second means is accomplished by a wedging effect between the first and second gliding means. Between the wedge surfaces in the first and second gliding means, there are roll surfaces, by means of which the movement of the horizontally moving, wedge-like second gliding means is transmitted to the second gliding means as a vertical movement and thus to the working movement of the tool in the buffer bar.
The solution known from the publications U.S. Pat. No. 5,092,151 and U.S. Pat. No. 5,199,293 is disadvantageous in the respect that the approaching movement and the working movement are arranged to be effected by separate means and actuators using them. In consequence, firstly the construction using such a method is complex and expensive, because of the high investments on the required equipment; second, a complex control, system is required for the successive approaching and working movements, which may easily cause operational risks.
It is an aim of the present invention to eliminate the above-mentioned disadvantages of prior art and thus to improve the level of technology in the field.
More particularly, the instant invention sheet fabrication machine is a new generation machine that, instead of hydraulics, utilizes servo motors for activating the sheet fabrication mechanisms, such as for example the coacting tool and die for effecting work on a worksheet. To provide movement for the upper tool, a servo motor with sufficient torque drives a contact mechanism, in the form of a roller, for example, moveable along the direction parallel to the plane of the worksheet, referenced simply as the x axis, for example. The top of the ram to which the roller makes contact is configured such that when the roller is driven by the servo motor to move to a given position along the x axis, the ram is driven in a vertical direction for a given distance. The configuration of the top portion of the ram, which together with the tool may simply be referred to as the tool means, is particularly configured to have at least one surface that, when it comes into contact with the roller, would actuate the tool to perform a number of innovative techniques, among which include, but not limited to, the punching of a worksheet, the measurement of the tool length, the presetting of a base point from which the work of the tool is referenced, and a forming operation on the worksheet.
The instant invention sheet fabrication machine also utilizes a servo motor for effecting the movement of the lower die, in a vertical direction relative to its corresponding upper tool. The mechanism for effecting the vertical movement of the die could be similar to that which effects the vertical movement of the upper tool, as the lower portion of the die is configured such that when the lower contact means, for example a roller, driven by the lower servo motor makes contact with the bottom portion of the die, vertical movement of the die is effected. Some of the configurations envisioned for the bottom portion of the die include the use of a wedge, a ring and a threaded portion all of which can coact with the servo motor, and its appropriate driving mechanism. Equivalents of the just mentioned configurations are also envisioned.
In addition to being able to measure the length of the tool and providing a setting from which the tool can reference its work, the present invention machine further includes software programmed thereto that provides logic that enables it to inform the operator that the punch tool within the tool assembly needs to be readjusted. Other logic features of the instant invention machine include xe2x80x9clook aheadxe2x80x9d functions that enable the machine to simultaneously accelerate and decelerate the tool and the worksheet so that optimal fabrication of the worksheet can take place. Further logics are provided to minimize the. noise that results from the tool coming into contact with the worksheet. With the appropriate logic and the proper configuration of hardware, deforming operation can also be performed by the lower die with great accuracy and no marking of the worksheet, as compared to when the worksheet is formed by the use of an upper tool.
Given that both the working tool and die each are driven by a servo motor, the instant invention machine, unlike the conventional hydraulics driven machines, can control the accuracy of how the sheet is worked to a much greater degree.
In addition to being provisioned with the appropriate software and hardware to optimize the operational speed and minimize the noise generated, the instant invention machine is also provisioned with an energy conservation system that enables the reuse or recycling of excess energy generated to thereby reduce its energy consumption. The instant invention machine furthermore is provisioned with a temperature maintenance system that monitors the operating temperature of the machine, and more specifically the various servo motors thereof, so as to ensure that the operating temperature of the machine does not exceed a predetermined overheating temperature for a predefined period of time, thereby preventing detriment to the machine.
The instant invention therefore provides an economical as well as ecologically friendly machine for sheet fabrication.
The instant invention further provides a machine that is capable of effecting different types of operations on worksheets by using servo motor driving mechanisms.
It is furthermore an objective of the present invention to provide a sheet fabrication machine that has the intelligence to xe2x80x9clook aheadxe2x80x9d in its fabrication of a worksheet so that the acceleration/deceleration of both the worksheet and the tool for effecting work on the worksheet are optimized.
It is moreover an objective of the present invention that the noise level resulting from the operation of the machine be minimized, as for example limiting the decibel (dB) of the noise of the machine to certain predefined limits.